When Judgment Day arrives, Legion is on the Celestial's chopping block! Is David Haller a hero, or will he succumb to his madness just as everyone predicts? Then, something savage is afoot! Nightcrawler develops some very demonic physical features - and he's not the only one. Goodbye, Warren Worthington III - and hello, murderous winged monster! Meanwhile, Banshee has developed a flaming skull, and Cypher and Warlock have made a startling discovery about the seemingly innocuous blooms floating out of the Astral Plane. As Kurt's inner beast threatens to completely take control, can the Legionnaires - with help from the mystical Black Knight - untangle this complex web of threats before it envelops mutantkind? When Legion battles Nimrod, the status quo will be completely shattered! Collecting LEGION OF X #6-10 and X-MEN: BEFORE THE FALL - SONS OF X.